This booking photo shows a clearly injured Roger Alan Fields from his October 6, 2012 arrest by Sarasota Police. Security video has shown the officer slamming Fields' face into a wall, which required him to get stitches at a hospital.
Sarasota, Florida -- A video that appears to show a police officer injuring a homeless man during an arrest has sparked an internal investigation at the Sarasota Police Department.
The video -- captured by a downtown Sarasota security camera last month -- first shows a security guard at a bus terminal getting into an argument with Roger Alan Fields.
WATCH: Security video of the incident
The guard eventually forces Fields to the ground and holds him there for several minutes until two uniformed police officers arrive.
Fields is sat down in a nearby chair and several more minutes pass. The video then shows Officer Derrick Gilbert walking over to Fields and putting his hand on Fields' shoulder. Fields appears to pull away slightly, but then the officer immediately forces him up and throws him face-first into a wall.
The Sarasota Herald-Tribune reports Fields had his head split open and was taken to the hospital to get stitches.
At the time, Fields was charged with disorderly intoxication in a public place, and resisting an officer: obstruction without violence.
On Thursday, City Manager Tom Barwin said he contacted SPD to immediately open an internal affairs investigation.
Officer Gilbert has been placed on administrative leave during the investigation.
Sarasota Police has recently been under fire for its treatment of the homeless. Earlier this month a judge threw out the case of a homeless man who was arrested for charging his cell phone in a public park.
The arresting officer told the man at the time of his arrest that "theft of city utilities will not be tolerated in this bad economy."
The ACLU, meanwhile, claims the police department fosters a "culture of contempt and abuse" toward the homeless and that officers had been known to engage in what they would call "bum hunting."